Process of distilling oils with volatile catalysts



March; 23 1926. 1,578,049

A. M D. M AFEE PROCESS OF DISTI LLING OILS WITH VOLATILE CATALYSTS Filed Jan. 20, 1922 2 Sheets-Sheet 1 March 23 1926.

A. M D. M AFEE PROCESS OF DISTILLING OILS WITH VOLATILE CATALYSTS Filed Jan. 20 1922 2 Sheets-Sheet 2 Patented Mar. 23, 1926.

UNITED STATES PATENT OFFICE.

I AL'MER MGDUFFIE MOAIEE, OF PORT ARTHUR, TEXAS, ASSIGNOR TO GULF REFINING COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF TEXAS.

PROCESS OF DISTILLING OILS WITH VOLATILE CATALYSTS.

Application filed January 20, 1922. Serial No. 530,580.

To all whom it may concern.

Be it known that I, ALMER MCDUFFIE Mo- Arnn, a citizen of the United States, residing at Port Arthur, in the county of Jefferson 5 and State of Texas, have invented certain new and useful Improvements in Processes of Distilling Oils with Volatile Catalysts, of which the following is a specification.

This invention relates to processes of dis- 1 tilling oils with volatile catalysts; and it comprises processes of preventing the catalyst employed in such distillation process from passing to the final or water cooled condenser and thus mixing with the final prod- 1 -uct, whether this product be very light hydrocarbons such as gasoline, or heavierhydrocarbons such as kerosene, spindle oils and the like.

In my prior and copending application Serial No. 792,615 filed September 30, 1913, I have described and claimed a process of manufacturing lower boiling hydrocarbons from higher boiling hydrocarbons with the aid of catalysts, mentioning particularly anhydrous aluminum chlorid as a useful catalyst in this connection. In such application I have described in converting gas oil into gasoline, for instance, heating a mixture of gas oil and anhydrous aluminum chloridto the temperature of ebullition orin other words distilling the same. This temperature is usually around 500 to 550 Fahrenheit depending upon the nature of the gas oil employed, the percentage, the age of the charge of catalyst used, etc. I have also described in said prior application the use of anhydrous aluminum chlorid on other heavy hydrocarbons, such as kerosene, etc., and I have described how at the distillation temperature the aluminum chlorid acts catalyticallyj to convert higher boiling hydrocarbons into lower boiling hydrocarbons and I have particularly pointed out that when the temperature of the vapors goingto the final or water cooled condenser is controlled so as not to exceed about 350 F. and condensed products liquefying above 350 degrees F. are

allowed to flow back to the still, I can secure sweet saturated lower boilin hydrocarbons I of the nature of gasoline entirely free from the aluminum chlorid in the final or water cooled condenser. If temperatures much above 350 F. exist at a point just prior to the final or Water cooled condenser vapors of the aluminum chlorid or aluminum chlorid in combination with the oils, will go forward to the final or Water cooled condenser.

This described backtrapping of the aluminum chlorid or of the aluminum chlorid and the higher boiling hydrocarbons to the still while permitting onward flow to the Water cooled or final condenser of the lighter hydrocarbons isan advantageous wa of performing the aluminum chlorid distillation process. It however involves some loss of heat; the amount of heat dissipated by the reflux condenser and the limitation of temperature on outflowing uncondensed vapors is sometimes inconvenient where higher boiling oils than gasoline are desired.

I have discovered that the aluminum chlorid and the higher boiling oils may be prevented from reaching the final or water cooled condenser by means of other expedients and this discovery enables me to manufacture with the aid of aluminum chlorid, lower boiling hydrocarbons with a relatively high end boiling point, higher than that of gasoline. In said prior application, I described that when the temperature of the vapors at the entrance to the water cooled condenser is maintained at' not above 350 F., with consequent refluxing back to the still of higher boiling hydrocarbons and aluminum chlorid or aluminum chlorid compounds with the oil, thefinal lower boiling hydrocarbons obtained in the final or water cooled condenser are sweet, saturated gasoline. And when this vapor temperature at the point mentioned is controlled around 300, that the final product is a particularly good gasoline.

However, controlling the vapor temperature at the point mentioned in the prior application naturally limits the end fboiling point of the final product secured, and since the end boiling point of gasoline is progressively rising with improvements in carburet ers adapted to handle heavier gasoline and since it is also desirable to manufacture a sweet saturated kerosene and sweet saturated spindle oils and the like by means of alumi-.

num chlorid from high boiling hydrocarbons, it is a desideratum in this art'to pro vide ways and means for securing a product having higher boiling point than gasoline and at the same time of preventing the alu-. minum chlorid and its compounds with the hydrocarbon from reaching the finalor water cooled condenser.-

I accomplish the results sought by takin advantage of the tendency of aluminum chIorid to form hydrocarbon compounds with the oils which can be scrubbed out of the vapors with oil. The vapors reaching the reflux condenser are those of oils lighter and more volatile than the oil supplied-in the charge; and in so far as the volatilized aluminum chlorid is in combination with oil hydrocarbons, it is in combination with these more volatile oils. Oil of less volatile character, such as that of the charge, removes aluminum chlorid from these vapors and takes it back to the still. In so operating, the requirement for a relatively low exit temperature for the vapors going to the final condensers no longer obtains; 1. e., higher boiling distillates can be obtained.

According to the present invention during the distillation of the higher boiling hydrocarbons in the presence of aluminum chlorid, I shower or spray or otherwise intimately contact higher boiling hydrocarbons advantageously hydrocarbons of the same general character as those initially used in the still, with the .vapors in the vapor space, of the still or in the vapor line or in one' or more preliminary condensers which may well be air cooled condensers. By this expedient I am enabled not only to flush back, so to s eak, the aluminum chlorid and its compoun s,-with heavier oils, so to speak, washing out all aluminum chlorid from the vapors, but I am enabled to take advantage of the heat of these vapors for heating the incoming oil before cooling the vapors in the vapor space of the still, in the vapor line'of the still, and in the preliminary condensers. But the cooling of the vapors by incoming oil is relatively unimportant as compared to their scrubbing action toward aluminum chlorid and therefore the incoming oil which is intimately contacted with the vapors in the vapor space of the still, in the vapor lines or in the preliminary condensers, may well be hot oil; but it is advantageously of the same genera'l character as the oil used ini tially in forming the bath in the aluminum chlorid distillation process.

There are several different methods of performing the process of my present invention and several different apparatuses which may be used. The main feature is intimately contacting the vapors of aluminum chlorid and oil so that there is condensation of aluminum chlorid taking place with consequent refluxing back to the still of aluminum chlorid and its compounds with the oil. And therefore in one method I may pass the vapors from the still to a chamber containing surface-giving packing such as pebbles, shot, balls, irregular metallic or other substances, and I may or may not in this instance use the incoming oil for the purpose of securing the same thorough contact. Heavy oil condensing on these surfaces presents an extensive area of contact to pro mote the washing or scrubbing of vapors passing such condenser fillings.

In the accompanying drawings are shown several forms of apparatus in which I may perform my process and within the purview of my invention.

Figure l is a diagrammatic view partly in section showing one form of still with appurtenances Figure 2 is a similar view of the washing arrangement;

Figure 3 is a similar view of another washing arrangement;

Figure 4 is a detailed vertical section of a fractionation column which may be used in combination with the apparatus shown in other figures.

Similar reference numerals designate corresponding parts throughout the several views where possible.

Referring to the drawings 1 indicates a still which may be of the type described in my said prior application No. 792,615. This may be a cheese box type still, the lower portion of which is heated by means of the fire box 2. It may be provided at the lower end with a drawofi' 3 for aluminum chlorid sludge which tends to settle to the bottom taining aluminum chlorid in a masked state,

so to speak. The activity of the aluminum chlorid is spent or partly spent depending upon the degree to which the process has been run. Ordinarily it is drawn off from the still in the form of a sludge and sent to suitable recovery apparatus for recovering the aluminum chlorid therefrom. This still 1 is provided with eflicient stirring mechanism 4 and with the oil inlet 5. This inlet may be provided with one or more branches, two (6 and-7) being shown and these two branches are advantageously provided with rose heads 8 and 9 for the purpose of spraying the incoming oil in the vapor space of the still. When fresh aluminum chlorid is to be added it is usually added in the form of a mixture of aluminum chlorid and warm oil and this may be done through the inlet 1y somewhat to the still and ending in a preliminary or reflux condenser 12. This is advantageously an air cooled condenser. At

the top of this air cooled condenser is the .chlorid and higher boiling hydrocarbons back to the still. And leading from the top of the preliminary air cooled condenser 12 is the vapor line 16 in communication with ,a second air cooled condenser 17. This second air cooled condenser has a backtrap line 18 in communication with the backtrap 15 so that condensates may thus reach the still. And leading from a high point of the air cooled condenser 17 is a vapor line 19 terminating in a coil 20 and in a water cooled condenser 21. The final product from 20 is sent to the receiver or storage tank not shown. I may use scrubbing apparatus shown by pipe 1 1' leading from line 5, and terminating in condenser 17 in spray head 8'. i

For purposes of observing the temperature the still may be provided with thermometer 22 in the mixed body of aluminum chlorid and high boiling oil although this is not necessary since the essential thing is to keep this mixture at aboiling temperature. The

vapor space of the still may be provided with thermometer 23 for observing the temperature and each of the air cooled condensers 12 and 17 may be provided with thermometers 24 and 25 for observation of temperature. However in the present invention the observation of the temperature is not as important as in the prior application No. 792,615, because according to the present invention reliance is placed upon the backwashing eifect of admitted higher boiling oils to the vapor space of the still and to the preliminary condensers to keep aluminum chlorid from going forward with vapors of lighter oils.

An efficient means and way of preventing the forward flow of vapors of aluminum chlorid and of its combinations with the oil, in addition to the sprays described is the mechanism shown in the Vapor line 11 at the top of the still." Oil may be tapped from the line 5 into this line by means of a jet or the like 26 and under a more or less elevated pressure if desired, or the jet ending in a spray nozzle may be advantageously directed toward the still so that all vapors in the vapor line leading to the first condenser are intimately contacted with incommg oil.

In the operation of theprocess as willbe more fully hereinafter described the second air cooled condenser will contain no aluminum chlorid although it may contain the vapors of gasoline, kerosene, spindle oil and the like, depending upon the operation of the process. Therefore this second condenser 17 which I have shown as an air cooled condenser, may well be a fractionating col umn. That is tosay, it may be of considerable length and may be provided at points along its height with a plurality of outlets with partitions between, these partitions draining to each other. Condensates in the compartments formed by these different partitions may be'withdrawn with the result that from this fractionating 001- umn I may secure at the lower points the heavier condensates such as spindleoil, from an intermediate point, relatively heavy con densates such as kerosene, and from a high point relatively lighter condensates such as gasoline. In Figure 4 I have shown diagrammatically a form of fractionating column which may be used.

Referring to Figure 2, the preliminary air cooled condenser 12 may be filled with inert material such as rock fragments with irregular surfaces, refinery coke or shot or the like 25. In addition to this the preliminary condenser 12 may be provided with oil inlet 14: drawing oil from line 5 as is described with reference to Figure 1. The presence of the filler in this preliminary chamber acts to give intimate contact between the oil and the aluminum chlorid va pors arising from the still, and secure a better and quicker condensation. The vapors arising from the still contain those of relativelyheavy oils as well as of lighter oils and by this means of condensation, the aluminum chlorid is taken out with the former and does not pass forward with the latter through vapor line 16 leading to the next condenser. As stated, however, if desired, in addition to the use of the filling material in the preliminary condenser the incoming oil from the spray 13 may be used.

Figure 3 shows a somewhat different form of apparatus in which the still is repre-. sented diagrammatically and in which the vapor line 11 leading to the preliminary no condenser 12 is provided with the spray inlet 26. This may be in the form of a jet spray or the like if desired. In addition to this the still may be provided With the rose spray 6 and 7 inaccordance with F igure 1. The condenser 12 may also beprovided with the oil inlet 13 as in theother figures described. The device just described with respect to Figure 3 is also shown in Figure 1 wherein the same reference numerals designate corresponding parts.

F igure 4 is a diagrammatic viewof one form of fractionating column which may be used as the second condenser. It is shown diagrammatically in Figure 1. In Figure 1 this condenser may be merely a second air cooled condenser. ut where it is desired to immediately fractionate the products made from the aluminum chlorid distillation a fractionating tower or a device similar to that shown in Figure 4 may be used. This may be air cooled or insulated as the expediency of any particular case may demand. Figure 4 merely illustrates grammatically one form of device which may be employed. The vapors from the preliminary condenser 12 go by line 16 to the fractionating column and find their way upward through the openings 28 and around the baffie plates 2!) against downcoming condensate from higher sections. These vapors flow up past this plurality of partitions and baflie plates while condensates flow. downwardly. The condensates may be tapped ofi' continuously or from time to time through the line 19 from each'section leading to the final storage tanks. In this manner I am enabled to secure directly and separately from an aluminum chlorid distillation, higher boiling hydrocarbons such as kerosene, spindle oil and the like and relatively lower boiling hydrocarbons such as gasoline, and in fact I can fractionate the gasoline so that I may secure it with a relatively low end boiling point. I can fractionate any of these hydrocarbons to secure substances with a narrow range between theirinitial and end boiling points.

While I have described the process as ad-- vantageously applicable to the manufacture. of products with higher boiling points than gasoline, it is, of course, to be understood that this process may be run for the manufacture of gasolinealone refluxing backto the still all higher boiling hydrocarbons together with aluminum chlorid by aid of the incoming oil as described. The operation of the process and the apparatuses described are obvious from the foregoing.

Referring to Figure 1, the vapors in the vapor space of the still are scrubbed by incoming fresh oil either hot or cold from the sprays 8 and 9. The vapors going by vapor line 11 to preliminary condenser 12 are scrubbed by oil from the oil inlet 26 and where the second condenser is used as an air cooled condenser or.even as the fractionat'ing column, the vapors may be further scrubbed by means of the inlet 14 described. I have found, however, that the final scrubbing in the condenser 17 need only be resorted to in special instances, the'preliminary scrubbing removing all the aluminum chlorid in the vapors no matter whether they pass from the first preliminary condenser at temperatures higher than 350 F. In fact I have taken vapors from the preliminary condenser at temperatures above 500 to 550 F. as registered by thermometer 24:,

entirely free of aluminum chlorid and of its compounds with the oil. The vapors in the vapor space of the still are very efiectually scrubbed and freed from aluminum chlorid by the sprays 8 and 9 although at times pardiaticularly when running at a very rapid rate, the additional or auxiliary scrubbers shown by inlets 26 and 14 are useful.

Figure 2, intimate contact between the oil and the vapors is secured by means of the system will prevent the passage of aluminum chlorid to the water-cooled condenser. It is desirable in admitting the scrubbing oil to use substantially ordinary pump pressure,

.but, particularly when the still is run at more than atmospheric pressure, the scrubbing oil may be admitted at a higher pressure. However I may admit the scrubbing oil at relatively high pressure even when the aluminum chlorid distillation process is be ing run at atmospheric pressure or under vacuum.

While I have mentioned anhydrous aluminum chlorid as the catalytic agent to be employed it is to he understood that other volatile catalytic agents may be used such for instance as iron chlorid, zinc chlorid, tin chlorid, antimony, pentachlorid, selenium oxychlorid, and others. I have found that the metallic halides are particularly useful although aluminum chlorid is the best so faras at present known.

Usually from 5 to 10 per cent by weight of aluminum chlorid calculated on the weight of the oil in the still is a good proportion to use in distillation. Oil and aluminum chlorid may be constantly ad mitted to the still, and the heavy sludge of oil and aluminum chlorid may be removed continuously or from time to time, from the bottom of the still. What I claim is 1. The process of distilling higher boiling oils with metallic halides which comprises heating a mixture of a metallic halide and higher boiling oil to distil the same, conducting away vapors of lower boiling oils formed, condensing the Vapors of lower boiling oils and intimately contacting the said vapors prior to their condensation with added petroleum hydrocarbon.

2. The process of distilling higher boiling oils with metallic halides which comprises heatng a mixture of a metallic halide and higher boiling oil to distil the same,

conducting away vapors of lower boiling oils formed, condensing the vapors of lower boiling oils and intimately contacting the said vapors prior to their condensation with added petroleum hydrocarbons of the same character as that being distilled.

- the said vapors prior to their condensation with added petroleum hydrocarbon.

4. The process of distilling higher boiling oils with aluminum chlorid which comprises heating a mixture of. aluminum chlorid and higher boiling oil to distil the same, conducting away vapors of lower boiling oils formed, condensing the vapors of lower bo1l ing oils and intimately contacting the said vapors prior to their condensation with added petroleum hydrocarbons of the same character as that being distilled.

5. The process of distilling gas oil with aluminum chlo'rid which comprises heating a mixture of gas oil and aluminum chlorid to distil the same, conducting away vapors of lower boiling oils formed, condensing the vapors of lower boiling oils and intimately contacting the said vapors prior to their condensation with added petroleum hydrocarbon.

6. In the distillation of higher boiling petroleum hydrocarbon with anhydrous aluminum chlorid the process which comprises intimately contacting the vapors formed by such distillation with added petroleum hydrocarbon to scrub such vapors and eliminate aluminum chlorid, and condensing the vapors thus freed of aluminum chlorid.

7 In the distillation of gas oil with aluminum chlorid the process which comprises intimately contacting the vapors formed by such distillation with added petroleum hydrocarbon to scrub such vapors and eliminate aluminum chlorid and condensing the vapors thus freed of aluminum'chlorid.

8. In the manufacture of lower boiling hydrocarbons from higher boiling hydrocarbons with the aid of aluminum chlorid,

the process which comprises distilling such higher boiling hydrocarbons in the presence of anhydrous aluminum chlorid, conducting the vapors formed by such distillation to a preliminary condenser, and contacting the vapors in said preliminary condenser with added petroleum hydrocarbon for the purpose of removing from said vapors aluminum chlorid carried forward in said distillation, refluxing backto the still eliminated aluminum chlorid together with the added scrubbing oil.

9. In the manufacture of lower boiling ing to a final condenser,

hydrocarbons from higher boiling hydrocarbons with the aid of aluminum chlorid, the process which comprises distilling such higher boiling hydrocarbons in the presence of anhydrous aluminum chlorid, scrubbing the vapors formed by distillation with added petroleum hydrocarbon'to remove aluminum chlorid, conducting the said vapors, to a preliminary condenser and contacting the vapors in-said preliminary condenser with added petroleum hydrocarbon for the purpose of removing from said vapors alu1ninum chloridcarried forward in said distillation, and refluxing back to the still eliminated aluminum chlorid together with the scrubbing oil,

10. The simultaneous manufacture of different grades of lower boiling hydrocarbons from higher boiling hydrocarbons with the aid of aluminum chlorid which comprises distilling the higher boiling hydrocarbons in the presence of aluminum chlorid, passtion through a vapor line ultimately leadand passage of such vapors intimately conin the ing the vapors resulting from such distillatacting them with added higher boiling hydrocarbons thus scrubbing out aluminum chlorid pre ent in said vapors, "refluxing back to the gtill such scrubbed out aluminum chlorid and higher boiling oils, and fractionating and condensing such vapors which have been thus scrubbed.

11. The simultaneous manufacture of different grades of lower boiling hydrocarbons from higher boiling hydrocarbons with the aid of aluminum chlorid which comprises distilling the higher boiling hydrocarbons in the presence of aluminum chlorid, passing the vapors at temperatures above 350 F. in the vapor line ultimatelyleading to a final condenser, and in the passage of such vapors intimately contacting them with added higher boiling hydrocarbons thus scrubbing out aluminum chlorid present in said vapors, refluxing back to the still such scrubbed out aluminum chlorid and higher boiling oils, and fractionating and condenspassing the vapors at temperatures above 350 F. in thew-vapor line ultimately leading to a final condenser, and in the passage of such vapors intimately contacting them with added higher boiling hydrocarbons thus scrubbing out aluminum chlorid present insaid vapors, refluxing back to the still such scrubbed out aluminum chlorid and higher boiling oils, fractionating and ..condensing bons in the presence of aluminum chlorid,

I carbons while ontheir way to the final condenser and delivering such contacted vapors to a final condenser for condensation.

14. In the distillation of higher boiling hydrocarbons with a volatile catalyst, the

process of contacting vapors of the oil containing the catalyst prior to their delivery to the final condenser with liquid hydrocarbons delivered from an outside source, delivering such contacted vapors to a final condenser for condensation and returning to the mixture undergoing distillation the liquid oil and the catalyst which has been scrubbed out of the vapors.

l5. Inthe distillation of higher boiling hydrocarbons with aluminum chlorid, the process of passing the vapors of distillation to a final condensing apparatus, and in such passage intimately contacting such vapors with hydrocarbon oil delivered in substantial counter-current to the flow of vapors to remove aluminum chlorid from the vapors. and returning such removed alumi num chlorid to the higher boiling hydrocarbons undergoing distillation. I

In testimony whereof, I have hereunto affixed my signature.

ALMER MoDUFFIE MoAFEE. 

